Very often we do not relate certain actions with their consequences on health, but that is what doctors and the rest of the scientific community are for, who ask questions and try to prove hypotheses.
Precisely, a team from the Rovira i Virgili University (URV) has set out to demonstrate if there was any relationship between a health habit that all medical institutions recommend and a higher degree of cognitive impairment, in more than 7,000 people over 55 years.
Jordi Salas-Salvadó is a professor of nutrition and director of the Human Nutrition Unit at the URV, and one of the researchers who participated in the study, which is part of a larger epidemiological work.
"What we did is evaluate the participants' food and drink consumption to see if it could be related to the disease," explains the doctor. "There were already some studies that show that older people can be especially affected during episodes of heat and dehydration. It has been seen that this dehydration, if severe, leads to alterations in cognitive status: memory, reaction capacity, etc."
Salas-Salvadó's team wanted to contrast these findings with the population they were working with, who were people between 55 and 60 years old. But they wanted to do it in a way closer to reality: those situations in which you are not completely dehydrated, but your hydration level is not optimal either.
The URV scientists saw that, looking at what they consumed, these people who were less hydrated had a greater risk of cognitive deterioration over time.
"So we can say that it is very important to have good hydration to have a good cognitive state," advises the doctor, according to the research that his team has carried out, with statistically significant results.
To evaluate the cognitive status of the participants, the authors administered a total of eight different tests. “By looking at the different components of cognitive state, we determine what we call global cognitive state,” she says. "What we were unable to determine is whether this was due to the water drunk or other types of liquids, and we did not find a statistically significant relationship: the state of hydration is the set of inputs and outputs of liquids in the body."
The European Food Safety Authority (EFSA) recommends drinking two liters of water daily for women and 2.5 liters for men. "These are recommendations based on current evidence. We saw that this amount was ingested by approximately 80% of the people we saw," says the expert. "It is very important to adhere to these recommendations, which are average recommendations: in situations of heat or significant exercise, this amount would increase."
